Steering Damper for Griso

[ginkgo]

Hey Griso riders, I installed an Ohlins steering damper on a Griso and wanted to share how I did it. I know Guzzis are inherently stable, but any motorcycle can have a speed wobble. I had a full-on tank slapper on a cruiser that nearly did me in, so I want dampers for peace of mind. The best part of this install is it uses off the shelf parts with no fabrication.

I used a Polaris ATV clamp on the left frame tube [part number 2878906], Fast From the Past 53mm fork tube clamp on the left fork leg [part number ODM-53], and an Ohlins damper with 140mm stroke [part number SD 004]. The Polaris clamp has a ½” hole so you will also need an aluminum spacer from Aluminum Spacers.com [part number AS50-16-26] to reduce the hole to 8mm for the bolt through the damper’s heim joint. Note: the Polaris hole is undersized by a thousandth so you’ll need to run a ½” drill bit through it to open it up for the spacer. Cut out a piece of bicycle inner tube and use it as a cushion/shim under the Polaris clamp. It helps get a really snug fit. Use blue LockTite in all the right places and you’ll be good to go.

Here are photos showing the fitment. I have some extra spacers and would be happy to share them at no charge; just send me your address and I’ll send you one.

 

[Steak]

Not that it can't happen I suppose, but I have never once heard a single report of a tank slapper on a GRiSO. I think some folks have noticed a bit of squirreliness after dropping the triple trees lower than might be advised, but that's about it.

I have however been witness to a non-standard mounting of an OHLINS damper on a V-11 LeMans that took a turn for the worse. One of the mounting points broke off and as a result the loose damper jammed within the fairing and held the bars in full lock during a low speed maneuver <4 MPH causing an unexpected dump resulting in a serious tib/fib fracture.

Not that your mounting method suggests the mounts will be subject to any undue stress, but the GRiSO was never fitted with a damper for good reason.

Great write up of the process though.

 

[DungeonMaster]

What?
Steak?
Here?

Yes, actually, I do want a steering damper for my Griso.
I also want to dispose of the stock handlebar and put on Aplila Falco sport-touring clip-ons.
Last time I had an "off" on a bike the bars shook out of my hands and I got five fractured ribs out of it.

Thanks for the OP.

DM

 

[Indefatigable]

I think Todd can get a unit that mounts right up on the handlebar riser. Looks real neat.

 

[GTM®]

I think Todd can get a unit that mounts right up on the handlebar riser. Looks real neat.

I tried with Matris, and they didn't offer anything yet. There's probably a few other options for retro-fit as well though outside of Matris.

 

[ginkgo]

As as result of my speed wobble I met one of America's premier vehicle dynamics engineers, who had personally investigated countless speed wobbles. The list of bikes that came to catastrophic ends would surprise you, as it included those that would "never" do such a thing. Speed wobble is the least understood phenomenon in motorcycling, with most advice on the topic simply repetition of previous unproved theory. In my case, the handlebars oscillated at 10+ cycles per second, emitting a loud hum, cutting my hands and fingers severely through leather gloves, ending in a vicious high-side at 70 mph, which injured lots more than my hands. Both right and left fork stops were broken off the steering head.

Manufacturers now furnish dampers on all sport bikes, due to their steep steering angles, but as recently as just a few years ago, such was not the case. Other bikes are equipped by the bean counters, who willingly delete what design engineers can't or won't defend.

I stayed away from riding for years because of my experience and sincerely hope to save others the same. You won't always hear about these things, unless you're an adjuster for a major insurer.

 

[GuzziMoto]

I too have experienced tank slappers. But most of them were on racebikes that already had a steering damper. One was on a street bike that had developed a puncture and the reduced air pressure in the rear tire apparently lead to a tank slapper, aka speed wobble. And one was caused by a steering damper (on a Guzzi, the steering damper was removed and the bike works fine now).
The moral of my story is that having a steering damper does not mean you won't/can't have a tank slapper. And that proper set up of the suspension, maintenance of the bike, and proper riding technique are your best defense against such things. If you want a steering damper, by all means put one one. Some bikes really do need a steering damper, mostly hard core sportbikes. But some extreme geometry bikes do not need one, like Buells (weird, but true). A modern Guzzi does not need one to be safely and properly ridden (some maintain that some older Guzzi's do), but if it makes anyone happy to mount one then do it. But if you do mount one please keep in mind the negative impact it will have as well as the positive impact, and keep it properly maintained and functioning.
Often mechanical devices (aka, tools) get blamed for failures that occur when said tools are used improperly.

 

[uzidzit]

A steering damper cannot "cause" a wobble or a weave, nor can it "fix" one geometry, weight distribution, and force cause them.

The Griso is prone to a little head shake under very hard acceleration, with a heavier rider. with CONSERVATIVE fork height. the easy fix is to get the correct spring rate and damping in the rear end and correct the forks (which are oddly over sprung and under damped) for most people.

Just part of the story on the griso suspension

 

[GuzziMoto]

A steering damper cannot "cause" a wobble or a weave, nor can it "fix" one geometry, weight distribution, and force cause them.

The Griso is prone to a little head shake under very hard acceleration, with a heavier rider. with CONSERVATIVE fork height. the easy fix is to get the correct spring rate and damping in the rear end and correct the forks (which are oddly over sprung and under damped) for most people.

Just part of the story on the griso suspension

While I completely agree that a steering damper does not "fix" anything, you are mistaken when you say a steering damper cannot cause a wobble or weave. If the damper or the mounting for the damper is not in 100% operating order it can definitely cause a wobble or weave. Anything that is attached to the steering/forks of the bike can have an impact on steering. I have seen poorly mounted dampers cause issues. I have also seen failing dampers cause issues. On my wife's V11 the stock OEM steering damper developed stiction, a reluctance to move. Once it started moving the stiction was reduced so it then moved ok. But the initial effort to get the forks to move was greater than the effort required to continue movement of the forks. This caused the bike to wobble and weave going down the road. You simply could not ride it without it wobbling and weaving at least a little, and under certain situations it wobbled and weaved a lot. To the point of being unsafe. Removal of the steering damper resolved the issue. No other changes were required. After my wife rode the bike without a steering damper she decided she preferred the way it steered without one. The steering was lighter and offered more feedback without the steering damper.
My Griso was not set up well from the factory. As mentioned, the spring and damper setting for the forks and shock were crap. I adjusted them to get the bike were I wanted it. Unlike many others I did not drop the front end but rather focused on keeping the rear from squatting so much. That keeps the entire bike off the ground more so that things don't drag so easily during cornering. It did not make sense to drop the front to match the rear but rather fix the rear to match the front. But there are many ways to set up suspension. Either way, my Griso did not shake the bars before I adjusted the suspension and it does not shake the bars now after I adjusted the suspension. With the geometry of the Griso, if it does shake the bars there is something wrong. It could be suspension, tire pressures, mechanical issues, or rider technique, but something is wrong. You can fix whatever is wrong, or you can put a steering damper on it. Putting a steering damper on it does not mean that it is not still wrong and it does not mean that you will not have a problem. But you may feel better about the heavier steering the bike has and develop a (false) sense of security.
To each their own.

 

[uzidzit]

If the damper or the mounting for the damper is not in 100% operating order it can definitely cause a wobble or weave. Anything that is attached to the steering/forks of the bike can have an impact on steering. I have seen poorly mounted dampers cause issues. I have also seen failing dampers cause issues. On my wife's V11 the stock OEM steering damper developed stiction, a reluctance to move. Once it started moving the stiction was reduced so it then moved ok. But the initial effort to get the forks to move was greater than the


So back to the point ALL every one ever two track vehicles no matter how they are set up weave at some condition, and or combination of speed accel load etc. ALL of them, setting one up only takes care of 99% of the time. and gives a margin...but as you said your problem was NOT with the damper it was with a SCREWED UP damper, you would have likely had the same result with brinelled steering head bearings that had been tightened to compensate or rusted till solid. your issue was one with BAD parts malfunctioning.

For the record I do not run a damper on my griso or stelvio but do run one on my old sport and on my gixxer and weestrom. It has to be done well and correct and if it is it causes no issues.

More modern active type dampers are actually very very useful, on dual sports when you clip a hidden root, on a street bike when a Turkey flies out from a bush and hits your hand guard at full lean in a sweeper. and the bars momentarily lock rather than do a single full oscillation tank slap. it can make the difference between getting pitched off and just riding through albiet in a really ugly fashion.

Really the only reason more bikes do not have then from the factory is cost, they also can add the feeling of weight or drag to the steering and when set poorly sluggishness, when broken problems. But most folks that have been around working on bikes a long time also bitch about using ball bearings for headstock bearings. The bike makers do not do it just to be cheap guys, they have a lighter more precise feel in steering than tapered rollers....but 99.999% of folks will give up the better feel of ball bearings in the steering head for the durability or rollers. (ps one of the other factors on the bike above that made the issue worse was if the stock handlebars were still in place, they were very very flexible...I always thought dangerously so ,I saw several bent during normal use)

point is if ya pick one use a good damper mount it well, and Maintain IT!!!! ie change the oil every year check the mounts etc. and use an active hydraulic type. not an old fashioned oem tube full of orings and slime.

Cheers

 

[johnno]

I think you did a tidy job with damper on griso .I had a griso and even on track never considered fitting one but if it helps you then fair enough . My 1100 sport had a steering damper as standard and after a few rides the first thing I did was take it off . interesting read this post